The present invention relates to the detection of glue applied to tipping paper used to secure filters to cigarette tobacco rods. More particularly, the present invention is directed to a method of and system for measuring in real time the amount and location of tipping glue coated on tipping paper used with the cigarette tipping portion of a cigarette making machine.
In the manufacturing process for making cigarettes using a typical automatic cigarette making machine which operates at nominal speeds of 8,000 cigarette rods per minute and above, one of the cigarette manufacturing steps involves the application of filter tips to a cigarette rod. As will be known to those of ordinary skill in the art, a cigarette rod of twice the length of the tobacco portion of a cigarette is supplied to the cigarette tipping portion of the cigarette making machine. This double length tobacco rod is cut in half to form cigarette length rods and the two rods are then separated from each other such that a double length filter tip can be placed between the two cigarette length rods. A piece of tipping paper, to which a suitable amount of tipping glue is applied, is caused to wrap around the two tobacco rod double filter assembly, thereby securing the double filter to the end portion of each of the two tobacco rods it contacts. As a last step, the double length filter is cut in half to form two filters, thus yielding two finished cigarettes.
Sometimes however, due to mechanical tolerances and other causes, an insufficient amount of glue is applied to the tipping paper such that, either during manufacture or before or during use of the finished cigarette, the filter separates or falls off from the tobacco rod portion of the cigarette. Investigation has revealed that a substantial percentage of the time the reason that the filter separates from the tobacco rod is that an insufficient amount of glue was applied to the tipping paper so that it did not securely hold the filter to the tobacco rod.
It would therefore be desirable to be able to measure the amount and location of the tipping glue applied to the tipping paper so that any finished cigarette manufactured with an insufficient amount of glue on the tipping paper with which to hold the filter to the cigarette rod can be prevented from leaving the cigarette manufacturing plant. It would also be desirable to be able to reject any such defective cigarettes downstream from the tipping portion of the cigarette making machine when it has been determined that an insufficient amount of glue was applied to the tipping paper. It would likewise be beneficial to utilize as much of the existing cigarette manufacturing machinery as possible to accomplish those goals.